System for operating mobile robot based on complex map information and operating method thereof

ABSTRACT

Disclosed are a system for operating a mobile robot based on cleaning area information and a method thereof. A mobile robot based on cleaning area information according to an exemplary embodiment of the present invention includes a memory which stores a plurality of cleaning area information in which at least a part of a cleaning available area is changed; and a controller which controls to select one cleaning area information among the plurality of stored cleaning area information, recognize a position on a cleaning area map which configures the selected cleaning area information and perform cleaning on the cleaning available area from the recognized position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and the benefit of Korean PatentApplication No. 10-2016-0007244 filed in the Korean IntellectualProperty Office on Jan. 20, 2016, Korean Patent Application No.10-2016-0114021 filed in the Korean Intellectual Property Office on Sep.5, 2016, and Korean Patent Application No. 10-2017-0000350 filed in theKorean Intellectual Property Office on Jan. 2, 2017, the entire contentsof which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a mobile robot, and more particularly,to a system for operation of a mobile robot using a composite ofplurality of different types of cleaning area information according tothe operation environment, and a method thereof.

BACKGROUND ART

Initial cleaning robots performed random cleaning while traveling bythemselves, and there were areas wherein cleaning could not be performeddue to the presence of obstacles and/or the condition of the floorsurface.

In order to compensate for this, techniques have been developed toperform cleaning based on a map, and such map-based cleaning robots areoperated in two main ways.

In the first method, the cleaning robot uses a map stored internally toperform cleaning and transmits the cleaning progress or completionstatus to a user terminal. In the second method, the cleaning robotprovides the user with its internally stored map, and the user then usesthe received map to transmit commands.

However, since the existing such map-based cleaning robots use only onemap, inconvenience can be incurred because a new cleaning map needs tobe created whenever the working environment changes in order to performcleaning.

SUMMARY OF THE INVENTION

In order to solve the above-mentioned problems in the existingtechnology, the aim of the present invention is to provide a system foroperation of a mobile robot which creates a composite of a plurality ofdifferent types of cleaning area information obtained from a cleaningarea map representing the cleaning area, a feature point map forrecognizing a position within the cleaning area, and option informationset by a user in order to perform cleaning while recognizing theposition through selective use of the composite of cleaning areainformation, and a method thereof.

However, the object of the present invention is not limited to the abovedescription, and other objects, which have not been mentioned above,will be more apparent to those skilled in the art from a reading of thefollowing description.

In order to achieve the above-mentioned aim, according to an aspect ofthe present invention, a mobile robot which moves based on a compositeof map information may include: a memory which stores a plurality ofcomposites of cleaning area information in which at least part of theavailable cleaning area is changed; and a controller which controls theselection of one composite of cleaning area information from among theplurality of stored composites of cleaning area information, recognizesits position on a cleaning area map which is constituted by the selectedcomposite of cleaning area information, and performs cleaning of theavailable cleaning area from the recognized position.

Further, the above-mentioned composites of cleaning area information mayinclude a cleaning area map representing the available cleaning area, afeature point map of feature point information for recognizing theposition within the cleaning area map, and option information set by auser.

Further, the controller may obtain an image while moving from a firstposition to a second position in a preconfigured manner according to acontrol command from the user, extract feature points from the obtainedimage to construct a temporary feature point map using the extractedfeature points, and compare the constructed temporary feature point mapwith each feature point map constituting the stored plurality ofcomposites of cleaning area information to allow selection of thecomposite of cleaning area information constituted by the feature pointmap having the highest matching rate as a result.

Further, the controller may calculate odometry information using inertiainformation obtained according to the movement from the first positionto the second position, predict the point of movement based on thecalculated odometry information, and compare the temporary feature pointinformation obtained at the predicted movement point with feature pointinformation constituting the feature point map obtained from themovement point and the vicinity of the movement point, as a resultdetermining the position within the cleaning area map of the compositeof cleaning area information corresponding to the feature pointinformation having the highest matching rate as the second position.

When the second position is determined, the controller may update thecleaning area map of the composite of cleaning area information to havethe area where the cleaning robot moved from the first position to thesecond position as a completed area, and control the mobile robot toperform cleaning of the available cleaning area from the second positionin the updated cleaning area map, and further update the performanceresults.

Further, the controller may extract preconfigured geometric informationfrom the constructed temporary feature point information map and, basedon the extracted geometric information, compare the temporary featurepoint map with the feature point maps constituting each of the storedplurality of composites of cleaning area information to select thecleaning area information constituting the feature point map which hasthe highest matching rate as a result.

When information for a wireless router is received from user equipment,the controller may wirelessly connect the mobile robot to the wirelessrouter based on the received wireless router information.

Further, the controller may operate in a first mode to serve as awireless router which may connect wirelessly to the user equipment, andwhen information for a wireless router is received from the userequipment, halt the first mode operation, after which it may operate ina second mode for connecting the user equipment to the wireless routerbased on the received wireless router information.

According to another aspect of the present invention, the system foroperating a mobile robot may include: a wireless router which isdeployed in the space where a mobile robot is located to connectwirelessly to the mobile robot; and user equipment which transmitscontrol commands to the mobile robot through the wireless router andreceives information on the area where cleaning has been completed aswell as composite cleaning area information while the mobile robotperforms cleaning, based on the previously stored cleaning areainformation.

Further, the user equipment may activate a mobile application throughwhich information may be transmitted to the mobile robot regarding awireless router to which the mobile robot is to be connected.

Further, the user equipment may transmit a control command to the mobilerobot to be provided with the previously stored plurality of compositesof cleaning area information from the mobile robot as a responsethereof, and when one composite of cleaning area information is selectedby the user from among the plurality of provided cleaning areainformation, may provide the selected result to the mobile robot.

According to yet another aspect of the present invention, the method foroperating a mobile robot may include: selecting one composite ofcleaning area information from among the previously stored plurality ofcomposites of cleaning area information according to a control commandfrom the user; recognizing the position within a cleaning area mapconstituted by the selected composite of cleaning area information; andwhile performing cleaning of the available cleaning area on the cleaningarea map starting from the recognized position, updating the cleaningarea map to include the area where cleaning has been completed as aresult of the cleaning performance.

In the selecting, an image may be obtained while performing cleaningfrom a first position to a second position in a preconfigured manneraccording to the control command, feature points may be extracted fromthe obtained image to construct a temporary feature point map of theextracted feature points, and the constructed temporary feature pointmap may be compared with the feature point map constructed from each ofthe stored plurality of composites of cleaning area information toselect the cleaning area information constituting the feature point maphaving the highest matching rate as a result.

In the recognizing, odometry information may be calculated using inertiainformation obtained according to the movement from the first positionto the second position, a point of movement may be predicted based onthe calculated odometry information, temporary feature point informationobtained at the predicted movement point may be compared with featurepoint information constituting the feature point map obtained from themovement point and in the vicinity of the movement point, and as aresult, the position within the cleaning area map of the cleaning areainformation corresponding to the feature point information having thehighest matching rate may be determined as the second position.

In the updating, when the second position is determined, the cleaningarea map of the composite cleaning area information may be updated toinclude an area where cleaning has been completed from the firstposition to the second position, and cleaning may be performed on theavailable cleaning area starting from the second position in the updatedcleaning area map, after which the performance results are updated.

As described above, according to the present invention, it is possibleto generate a plurality of composites of cleaning area information of acleaning area map representing the cleaning area, a feature point mapfor recognizing the position within the cleaning area, and optioninformation set by a user, and to perform cleaning while recognizing theposition through selective use of the generated plurality of compositesof cleaning area information, thereby minimizing user intervention dueto change of the working environment.

Further, according to the present invention, when the mobile robotmoves, the position in the cleaning area is recognized using the featurepoint information so that the difference between the actual position andthe position on the map may be minimized.

Furthermore, according to the present invention, when the mobile robotmoves, cleaning is performed even while performing the process ofrecognizing the position in the cleaning area, thus allowing increase ofthe cleaning efficiency while shortening the cleaning time.

The foregoing summary is illustrative only and is not intended to be inany way limiting. In addition to the illustrative aspects, embodiments,and features described above, further aspects, embodiments, and featureswill become apparent by reference to the drawings and the followingdetailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating a schematic configuration of a cleaningenvironment and system, according to an exemplary embodiment of thepresent invention.

FIG. 2 is a view illustrating a network setup process, according to anexemplary embodiment of the present invention.

FIG. 3 is a view illustrating a peer-to-peer connection structure,according to an exemplary embodiment of the present invention.

FIGS. 4A and 4B are views for explaining an information exchangeprinciple, according to an exemplary embodiment of the presentinvention.

FIG. 5 is a view for explaining a driving/cleaning control function,according to an exemplary embodiment of the present invention.

FIGS. 6A and 6B are views for explaining a map information checkingfunction, according to an exemplary embodiment of the present invention.

FIGS. 7A, 7B and 7C are views for explaining a cleaning area settingfunction, according to an exemplary embodiment of the present invention.

FIGS. 8A and 8B are views for explaining a cleaning schedule settingfunction, according to an exemplary embodiment of the present invention.

FIGS. 9A and 9B are views for explaining composites of cleaning areainformation, according to an exemplary embodiment of the presentinvention.

FIG. 10 is a view illustrating a method of performing cleaning,according to an exemplary embodiment of the present invention.

FIG. 11 is a view for explaining a position recognition process,according to an exemplary embodiment of the present invention.

FIG. 12 is a block diagram of a mobile robot, according to an exemplaryembodiment of the present invention.

It should be understood that the appended drawings are not necessarilyto scale, presenting a somewhat simplified representation of variousfeatures illustrative of the basic principles of the invention. Thespecific design features of the present invention as disclosed herein,including, for example, specific dimensions, orientations, locations,and shapes will be determined in part by the particular intendedapplication and use environment.

In the figures, reference numbers refer to the same or equivalent partsof the present invention throughout the several figures of the drawing.

DETAILED DESCRIPTION

Hereinafter, a system for operating a mobile robot based on compositecleaning area information and a method thereof, according to anexemplary embodiment of the present invention, will be described withreference to accompanying drawings. Parts required to understand theoperation and effects of the present invention will be mainly describedin detail.

In the description of the components of an exemplary embodiment, acomponent having the same name may be denoted by a different referencenumeral in some drawings but may be denoted by the same referencenumeral in other drawings. However, even in this case, it does not meanthat the component has different functions depending on the exemplaryembodiment or that the components have the same function in thedifferent exemplary embodiments, but rather the function of each of thecomponents shall be determined based on the description of thecomponents in the corresponding exemplary embodiment.

The present invention generates a plurality of composites of cleaningarea information of a cleaning area map representing the cleaning area,a feature point map for recognizing the position in the cleaning area,and option information set by a user, and performs cleaning whilerecognizing the position through selective use of the generatedplurality of composites of cleaning area information according to auser's command.

In the exemplary embodiment of the present invention, a “mobile robot”refers to a robot that may travel, whether autonomously or according tocommands from a user. A mobile robot may include, for example, acleaning robot, a logistics transport robot for transporting industriallogistics, a service robot for transporting personal objects, such asfood, a military robot for serving a military purpose, or any otherrobot that may travel. Although exemplary embodiments of the presentinvention are described in connection with a cleaning robot, any othertype of mobile robot may also utilize the various aspects of the presentinvention.

FIG. 1 is a diagram illustrating a schematic configuration of a cleaningenvironment and system according to an exemplary embodiment of thepresent invention.

As illustrated in FIG. 1, the system according to an exemplaryembodiment of the present invention may include user equipment 100, amediation server 200, a wireless router 300, and a mobile robot 400.

The user equipment 100 connects to the mobile robot 400 through anetwork and displays various information provided by the mobile robot400 onto a screen, thus allowing a user to control the performance ofvarious functions based on the information.

In this case, the user equipment 100 may allow a user to control theperformance of various functions through a mobile application. Suchfunctions include a remote control function, a video call function, adriving/cleaning control function, a map information checking function,a cleaning status checking function, a cleaning area setting function,and a cleaning schedule setting function.

1) The remote control function is a function of using the user equipmentas a remote control for the mobile robot. In other words, the userequipment is used as an input/output device for controlling the mobilerobot instead of controlling the mobile robot by direct contact with themobile robot, which may not be practical.

2) The video call function is a function that allows a video call to beheld with a person in the vicinity of the mobile robot using a camera,microphone, and speaker installed in the mobile robot.

3) The driving/cleaning control function is a function that moves themobile robot or instructs it to clean.

4) The map information checking function is a function that transmitsmap information generated by the mobile robot, using, for example, atechnique such as SLAM (simultaneous localization and mapping), to theuser equipment to allow the user to view the map information.

5) The cleaning status checking function is a function in which themobile robot, based on the map information, transmits, to the userequipment, indications of areas already cleaned by the mobile robot,areas that are in the process of being cleaned by the mobile robot, andareas that are to be cleaned by the mobile robot, thus allowing the userto check the status of a cleaning operation.

6) The cleaning area setting function is a function which allows theuser to setup partial areas among the entire area where cleaning ispossible, that is, to specify areas in which entrance is prohibited orareas for intensive cleaning, for example, based on the map information.

7) The cleaning schedule setting function is a function which allows theuser to setup settings such as the days of the week for cleaning, andthe cleaning time.

The user equipment 100 is electronic equipment that may perform wirelesscommunications and facilitate the foregoing functions. For example, theuser equipment 100 may be a mobile phone, a smart phone, anotebook/laptop computer, a digital broadcasting terminal, a personaldigital assistant (PDA), a portable multimedia player (PMP), anavigation system, a netbook, or a tablet.

The mediation server 200 may connect to both the user equipment and themobile robot to provide each with information of the other. Suchinformation may include, for example, identification information andnetwork address information, thus enabling communications between theuser equipment 100 and the mobile robot 400 via the network.

The wireless router 300 is deployed in a position within a predeterminedrange of where the mobile robot 400 is to be deployed, and is connectsto the network so that information may be transmitted from the userequipment 100 to the mobile robot 400 and information may be transmittedfrom the mobile robot 400 to the user equipment 100.

Here, the wireless router 300 is a network equipment which is connectedto the Internet to enable a plurality of software devices to share oneInternet line for simultaneous access to the Internet throughtransmission of wireless signals. The wireless router 300 also serves asan access point to perform wireless communication within a wirelesscoverage area of a predetermined range to connect the mobile robot 400to the network.

The mobile robot 400 connects to the user equipment 100 through thenetwork and operates according to user commands provided by the userequipment 100 while providing various kinds of information to the userequipment 100.

In this case, the mobile robot 400 may be exemplified as a cleaningrobot, a hospital service robot, a logistics service robot, a militaryrobot, or an industrial robot, and the type of robot is not specificallylimited. However, in the following exemplary embodiment, therepresentative example of a cleaning robot will be mainly described.

Further, the wireless communication includes methods such as a wirelessLAN (WLAN), Wi-Fi, WiBro (wireless broadband), WiMAX (WorldInteroperability for Microwave Access), High Speed Downlink PacketAccess (HSDPA), Bluetooth, radio frequency identification (RFID),infrared data association (IrDA), ultra-wideband (UWB), Zigbee, 3rdgeneration (3G), 3rd Generation Partnership Project (3GPP), and LongTerm Evolution (LTE).

FIG. 2 is a view illustrating a network setup process, according to anexemplary embodiment of the present invention.

As illustrated in FIG. 2, when the mobile robot 400 is setup to serve asa wireless router, that is, to operate in the first mode (S201), theuser equipment 100 may directly connect wirelessly to the mobile robot400 (S202).

In this case, the mobile robot 400 has a network adaptor for connectingto the network. The network adaptor may be operated in the first mode toperform the function of a wireless router, that is, to perform as asoft-AP (software enabled access point) or in an infrastructure mode, ormay be operated in a second mode connection to the wireless router 300,that is, in a client mode.

Next, the user equipment 100 may activate a mobile application (S203).

Next, the user equipment 100 may transmit to the mobile robot 400information regarding a specific wireless router (e.g., wireless router300) to which the mobile robot is to be connected through the activatedmobile application, that is, information such as a service setidentifier (SSID), a security protocol, a security algorithm, or asecurity key (S204).

Next, the user equipment 100 may inactivate the mobile application(S205).

Next, when information for a specific wireless router is received, themobile robot 400 stops serving as a wireless router (S206) and sets thereceived information (S207) so that it may connect to a specificwireless router (S208).

In this case, after the user equipment 100 connects wirelessly to thewireless router (S209), the user equipment activates the mobileapplication and a user may control the mobile robot through theactivated mobile application (S210).

In this case, the user equipment 100 and the mobile robot 400 may needto exchange a large quantity of information, such as voice informationor image information, in real time. In the exemplary embodiment of thepresent invention, the user equipment 100 and the mobile robot 400 mayexchange such information through, for example, the mediation server 200or a peer-to-peer connection.

Here, an example of the case in which a peer-to-peer connection isapplied between the user equipment and the mobile robot will bedescribed.

FIG. 3 is a view illustrating a peer-to-peer connection structure,according to an exemplary embodiment of the present invention.

As illustrated in FIG. 3, the user equipment 100 and the mobile robot400 each obtain identification information and network addressinformation of the other from the mediation server 200 to establish apeer-to-peer connection.

In this case, the user equipment 100 and the mobile robot 400 are bothequipped with an interactive connectivity establishment (ICE) framework,which performs connection and communication through two ICE protocols.

Further, in order to establish the peer-to-peer connection, a SessionTraversal Utilities for NAT (STUN) server for obtaining informationregarding the network address information may be provided in addition tothe mediation server 200.

As described above, when the peer-to-peer connection is establishedbetween the user equipment 100 and the mobile robot 400, information,such as voice information, image information, and control information,may be exchanged therebetween. This exchange of information will bedescribed hereafter.

FIGS. 4A and 4B are views for explaining an exchange of informationbetween the use equipment 100 and the mobile robot 400 according to anexemplary embodiment of the present invention.

As illustrated in FIG. 4A, when control information is exchanged, if anevent is generated through input of the user of the user equipment 100,the mobile robot 400 generates a command corresponding to the event andtransmits the generated command to the user equipment 100 in the form ofnetwork packets through the peer-to-peer connection.

The user equipment 100 receives the command from the mobile robot 400through the peer-to-peer connection and interprets the received commandto perform an appropriate operation corresponding to the command

As illustrated in FIG. 4B, when a user of the user equipment 100 checkson an image or voice in the vicinity of the location of the mobile robot400, or when another user is present in the location of the mobile robot400, a voice call or video call may be performed.

For example, when voice information and image information are exchanged,the mobile robot 400 processes the image information input through itscamera and voice information input through its microphone and transmitsthe information to the user equipment 100 through the peer-to-peerconnection.

The user equipment 100 receives the voice information and the imageinformation from the mobile robot 400 and reversely processes thereceived voice and image information to regenerate said informationthrough an image output device (e.g., a display) and a voice outputdevice (e.g., speaker).

FIG. 5 is a diagram for explaining a driving/cleaning control function,according to an exemplary embodiment of the present invention.

In FIG. 5, a mobile application screen for controlling the mobile robot400 using the user equipment 100 is illustrated. The movement directionand driving request may be determined using the three buttons in thelower right portion of the screen.

For example, when the user presses one of the buttons, the userequipment 100 transmits, to the mobile robot 400 via the network, acommand for the mobile robot 400 to start traveling in the directioncorresponding to the pressed button. The mobile robot 400 interprets thereceived command and starts traveling in the applicable direction.

When the user releases the pressed button, the user equipment transmitsa command for the mobile robot 400 to stop. The mobile robot 400interprets the command and stops traveling.

Further, the user may select a cleaning mode through a menu or button.The cleaning mode may include, for example, an automatic mode in whichthe cleaning is performed automatically, a spot mode in which thecleaning is concentrated in a certain are areas, a turbo mode in whichthe cleaning suction force of the mobile robot 400 is strong, and asilent mode in which the cleaning suction force of the mobile robot isweak.

Further, the user may issue other commands for controlling the mobilerobot 400, such as to start cleaning command, a stop cleaning command,or a recharge the battery command, through the menu or buttons.

FIGS. 6A and 6B are views for explaining a map information checkingfunction, according to an exemplary embodiment of the present invention.

As illustrated in FIGS. 6A and 6B, the mobile robot 400 may generate amap based on the SLAM technique with images obtained through its camerawhile it moves. In this case, information collected from one or moresensors, such as an ultrasound sensor, a floor sensing sensor, aninfrared sensor, and a load current sensor, mounted on the mobile robotis may be used to generate a more accurate map.

Map information generated by the mobile robot 400 may be configured asan array of squares, and each square may include information foridentifying the shape of the area corresponding to the square. Theinformation for identifying the shape of the corresponding area mayinclude additional information, such as already cleaned areas, obstaclesaround which the mobile robot 400 cannot be moved, areas where the floorwas not detected such as a cliff, slippery areas, areas where the flooris carpeted, areas where there is a magnetic strip on the floor, andareas where the floor is covered in lots of dust.

The color of the square may vary depending on the information foridentifying the shape of the area.

The mobile robot 400 transmits the map information formed by arrays ofsquares generated or updated during cleaning to the user equipment 100so that the user equipment 100 may check the process of updating mapinformation in real time, thus allowing the user equipment 100 to gainan understanding of the cleaning status through the information includedin the map information.

In this case, the mobile robot 400 may transmit not only the previouslycompleted map information, but also map information which is in theprocess of being generated, as illustrated in FIG. 6A, or mapinformation which has been completely generated, as illustrated in FIG.6B.

When the mobile robot 400 has completed cleaning once, it obtains mapinformation for the entire area that was cleaned, and the obtained mapinformation may be referred to when the area is to be cleaned again.

FIGS. 7A to 7C are views for explaining a cleaning area setup function,according to an exemplary embodiment of the present invention.

As illustrated in FIGS. 7A to 7C, when the user equipment 100 displaysthe map information on the screen, the user may set, within thedisplayed map information, areas in which entrance of the mobile robot100 is prohibited as well as areas that may require intensive cleaning.

For example, the user may press a button on the display of the userequipment 100 to designate areas on the displayed map to which entranceof the mobile robot 400 is prohibited and areas that require intensivecleaning by touching the areas. As illustrated in FIG. 7A, when the userbriefly presses and holds on an arbitrary vertex of a rectangular areato be designated, drags a finger to an opposite vertex of therectangular area while holding the arbitrary vertex, and then releasesthe finger, the rectangular area is designated as the correspondingarea, as illustrated in FIG. 7B.

Information on the prohibited areas and intensive cleaning areas setupas described above is represented by rectangular areas on the map, andmay be configured by the coordinates of the left upper portion and theright lower portion of the rectangle.

As another example, when the user briefly presses and holds thepredetermined areas where entrance is prohibited or intensive cleaningareas after pressing the button for designating the prohibited areas andintensive cleaning areas on the map screen of the user equipment 100, amessage pops up asking whether to delete the settings, and the user maydelete the area setup through response to the message.

A plurality of areas where entrance is prohibited and intensive cleaningareas may be set as necessary, as illustrated in FIG. 7C.

FIGS. 8A and 8B are views for explaining a cleaning schedule setupfunction, according to an exemplary embodiment of the present invention.

As illustrated in FIGS. 8A and 8B, the mobile robot may perform cleaningat a scheduled time set by the user in addition to cleaning followingcleaning instruction signals directly issued by the user.

As illustrated in FIG. 8A, the user may set the time to start cleaningor the days of the week on which to perform cleaning on the screen forsetting up the cleaning schedule, and a plurality of schedules may bereserved, as illustrated in FIG. 8B.

When the cleaning schedule is reserved, the user equipment 100 transmitsa command corresponding to the reserved cleaning schedule to the mobilerobot 400 and the mobile robot 400 stores the cleaning schedule andperforms cleaning at the corresponding time on the corresponding day(s)of the week.

In this case, the mobile robot 400 performs the cleaning using thestored map; however, generally, when the mobile robot 400 moves to a newplace to perform cleaning, the mobile robot 400 creates a new map toperform the cleaning. Therefore, according to the exemplary embodimentof the present invention, rather than generating only one map, aplurality of different maps may be generated according to the workingenvironment, to be used selectively.

FIGS. 9A and 9B are views for explaining the composites of cleaning areainformation, according to an exemplary embodiment of the presentinvention.

As illustrated in FIGS. 9A and 9B, a plurality of maps are generated inthe exemplary embodiment of the present invention. Specifically, aplurality of composites of cleaning area information may be generated, acleaning area map representing the available cleaning area, asillustrated in FIG. 9A, a feature point map including feature pointinformation for recognizing the position within the cleaning area, asillustrated in FIG. 9B, and option information set by a user.

One composite of cleaning area information may include the cleaning areamap, the feature point map, or the option information.

The cleaning area map may be constituted by an array of squares for thetarget cleaning area. Each square may include information foridentifying the shape of the corresponding region.

For example, the cleaning area map stores information such as areaswhere the cleaning has been completed, information on obstacles, andinformation on the recharging station.

The feature point map is a map of feature point information forrecognizing the position of the mobile robot 400 in the cleaning area.The feature point information may include the coordinates of a featurepoint extracted from an image taken by a camera, for example. Suchfeature point information is generated for every square constituting thecleaning area map, and a plurality of feature point information may begenerated.

The option information is information configured by the user, and forexample, may include cleaning area information indicating areas forwhich entrance is prohibited and intensive cleaning areas, and cleaningmanner information indicating a movement pattern, a movement speed, andan order of cleaning.

Such a plurality of composites of cleaning area information may begenerated for the same location, and a plurality of such information mayalso be generated for different locations. For example, composites ofcleaning area information may be generated for each of the case in whichthe door of a room is closed and the case in which the door is notclosed, in the same location. Further, in the case of a duplexenvironment, composites of cleaning area information may be generatedfor every floor.

The cleaning area information may be map information that is created bythe mobile robot 400, but is not limited thereto, and may also be mapinformation provided through the user equipment 100.

FIG. 10 is a view illustrating a method of performing cleaning,according to an exemplary embodiment of the present invention.

As illustrated in FIG. 10, when a mobile robot, according to anexemplary embodiment of the present invention, receives a controlcommand, for example, a cleaning starting command from a user or userequipment (S1001), the mobile robot may check whether previously storedcleaning area information exists (S1002).

Next, when the cleaning area information exists, the mobile robot drivesin a searching mode to determine its position before starting thecleaning (S1003), and may obtain an image by moving in accordance with apredetermined method while performing cleaning starting from a firstposition according to the searching mode (S1004).

To be more specific, the driving environment of the mobile robot, suchas an indoor environment, may include various structures, and thestructures may be formed by repeated patterns. In the case where thedriving environment is formed from a repeated simple structure, it isdifficult to accurately estimate the current position of the mobilerobot only through the information obtained by the mobile robot in itsplace before starting the cleaning. Therefore, according to theexemplary embodiment of the present invention, information may beobtained through various methods.

For example, according to a first method, the mobile robot obtains animage from a camera while rotating in its place. Information extractedfrom the image obtained through the first method may have a highermatching rate with the map information than information obtained whenthe robot is stationary. However, the matching rate in indoorenvironments which have a simple repeated structure may still be low.

According to a second method, the mobile robot obtains an image from thecamera during the process of driving forward in a straight line afterrotating in place, and according to a third method, the first method andthe second method may be combined, and the mobile robot moves based onan actually used traveling pattern.

In this case, the mobile robot operates by a movement pattern which isthe same as in the case when cleaning is actually performed, butoperates at a lower speed than its actual movement speed in order toincrease the success rate of position recognition.

In contrast, when no cleaning area information exists, the mobile robotgenerates new composites of cleaning area information and may performcleaning based on the newly generated composites of cleaning areainformation (S1014).

Next, the mobile robot extracts feature points from the obtained image(S1005) and may generate a temporary feature point map consisting of theextracted feature points (S1006).

In this case, the feature points are mainly extracted from corners, roomcorners, or the edges of objects.

Next, the mobile robot may extract geometric information from among thefeature points which constitute the generated temporary feature pointmap, for example, the geometric shape and geometric correlation (S1007).

Next, the mobile robot compares the extracted geometric information withpreviously stored cleaning area information (S1008) to calculate thematching rate, indicating the degree of matching, as a result of thecomparison (S1009).

Next, the mobile robot may select one composite of cleaning areainformation having the highest calculated matching rate (S1010). Thatis, the mobile robot may determine that the area where the cleaning areainformation with the highest matching rate is generated is the cleaningarea wherein the mobile robot is currently located and is the targetcleaning area.

In this case, the matching rate may be calculated using a sum ofabsolute differences (SAD) or a sum of squared differences (SSD), but isnot limited thereto, and various other methods may also be used.

Next, the mobile robot loads the selected composite of cleaning areainformation and compares the feature point map constituting the loadedcleaning area information with the temporary feature point map torecognize a current second position (S1011).

That is, the mobile robot recognizes a position on the feature point mapwhich corresponds to the temporary feature point map from among thefeature point maps which constitute the loaded composite of cleaningarea information as the current second position.

In this case, the mobile robot does not compare the temporary featurepoint map with all the feature point maps which constitute the loadedcomposites of cleaning area information, but predicts a movement pointusing odometry information and compares feature point maps located inthe vicinity of the predicted movement point.

To this end, the mobile robot collects inertia information whileoperating in searching mode and calculates odometry information, thatis, the traveling distance and traveling direction, based on thecollected inertia information.

FIG. 11 is a view for explaining the position recognition process,according to an exemplary embodiment of the present invention.

As illustrated in FIG. 11, when the mobile robot operates in apredetermined manner while performing cleaning from a first position, R,in accordance with the searching mode to obtain an image, a movementpoint, P1, may be predicted using odometry information, that is, thetraveling distance, d, and traveling direction, θ.

In this case, the mobile robot may compare temporary feature pointinformation at a predicted movement point, P₁, with feature pointinformation from the feature point maps which constitute the actualcomposite of cleaning area information of said movement point P₁ and P₂,P₃, P₄, P₅, P₆, P₇, P₈, and P₉ in the vicinity thereof, to determine theposition P₂ found to have the highest matching rate as the secondposition.

Next, the mobile robot may overlap the areas where cleaning has beencompleted in the process of recognizing the second position onto thecomposite of cleaning area information (S1012). That is, the mobilerobot may update the composite of cleaning area information to includethe areas where cleaning was completed during the process of recognizingits position while following the searching mode.

As described above, because the mobile robot may check the area wherecleaning has already been completed during the position recognitionprocess, the cleaning time may be shortened and the cleaning efficiencymay be increased.

Next, the mobile robot may start cleaning from a second position withinthe composite of cleaning area information (S1013).

FIG. 12 is a diagram illustrating the detailed configuration of a mobilerobot, according to an exemplary embodiment of the present invention.

As illustrated in FIG. 12, a mobile robot 400, according to an exemplaryembodiment of the present invention, may include an image obtaining unit110, an IMU 120, a communicator 130, a controller 140, an audioinput/output unit 150, an image display 160, and a memory 170.

The image obtaining unit 110 is, for example, a camera, and is mountedto capture images of a predetermined region of interest. Here, theregion of interest may be an area that may be photographed using acamera mounted on the mobile robot.

The IMU 120 measures inertia information of the mobile robot, forexample, information such as the position and/or pose. The IMU 120 mayinclude, for example, a gyro sensor 121 and an acceleration sensor 122.

The gyro sensor 121 collects angular velocity information of the mobilerobot 400.

The mobile robot 400 according to the exemplary embodiment of thepresent invention distinguishes the pose or operational status of themobile robot 400 using three-dimensional angle information and iscontrolled using the distinguished pose or operation status, so that thegyro sensor 121 is preferably a triaxial sensor.

That is, the gyro sensor 121 may collect triaxial angular velocityinformation for an x-axis, a y-axis, and a z-axis.

The triaxial angular velocities of the x-axis, y-axis, and z-axis, whichare detected by the triaxial gyro sensor 121, are referred to as theroll, pitch, and yaw, respectively.

Specifically, rotation around the x-axis of the mobile robot is calledthe roll, rotation around the y-axis of the mobile robot is called thepitch, and rotation around the z-axis of the mobile robot is called theyaw.

The three-dimensional angular velocity information to be obtained in theexemplary embodiment of the present invention refers to the roll, pitch,and yaw.

The acceleration sensor 122 measures the gravitational acceleration andacceleration in accordance with the movement of the mobile robot 400.The acceleration sensor 122 may be a triaxial sensor, similarly to thegyro sensor 121.

That is, the acceleration sensor 122 may collect the accelerationinformation of three axes, including an x-axis, a y-axis, and a z-axis.

The communicator 130 connects with the user equipment 100 to transmitand receive various kinds of information. For example, the communicator130 may receive control commands from the user equipment 100 andtransmit map information to the user equipment 100.

The controller 140 drives a driving motor and a suction motor based onpreviously stored composite cleaning area information following acleaning start command to control the mobile robot 400 for theperformance of cleaning while moving.

The controller 140 obtains odometry information, that is, the travelingdistance and traveling direction, based on the inertia informationprovided by the IMU 120, predicts the movement point based on theobtained odometry information, and generates and updates the compositecleaning area information, which consists of a cleaning area map for thearea to be cleaned based on the predicted movement point, a featurepoint map, and option information.

The controller 140 selects one composite of cleaning area informationfrom among a plurality of composites of cleaning area information whichis stored in advance and controls the mobile robot 400 to performcleaning based on the selected composite of cleaning area information.In this case, the controller 140 operates in a searching mode fordetermining its position and obtains an image in accordance to thesearching mode, extracts a feature point from the obtained image,generates a temporary feature point map based on the extracted featurepoint, and compares the generated temporary feature point map withfeature point maps which constitute the plurality of previously storedcomposites of cleaning area information to select one composite ofcleaning area information as a result of the comparison.

The controller 140 predicts the movement point in accordance to themovement and compares the feature point information for the predictedmovement point with the selected feature point map which constitutes thecomposite of cleaning area information to recognize the currentposition, and controls the mobile robot to perform cleaning based on therecognized current position.

When cleaning is performed based on the composite cleaning areainformation, the controller 140 may generate a cleaning area which isdifferent from the available cleaning area within the cleaning area mapwhich constitutes the composite cleaning area information. Therefore,when the area where cleaning is completed on the cleaning area map whichis newly generated after the completion of cleaning is larger than theavailable cleaning area within the original cleaning area map, thecontroller 140 may determine that the newly generated cleaning area mapis more suitable for the user environment, and may store the newlygenerated cleaning area map and delete the existing cleaning area map.

When a control command is received from the user equipment 100, thecontroller 140 controls the mobile robot 400 according to the receivedcontrol command. For example, the controller 140 controls the movementdirection and the moving speed, and controls the mobile robot 400 tostart or stop cleaning according to the control command for thedriving/cleaning control function.

As another example, the controller 140 may provide a plurality ofpreviously stored composites of cleaning area information to the userequipment 100 according to the control command for the map informationchecking function.

As yet another example, the controller 140 may transmit information suchas the areas in the process of cleaning, areas cleaned during movement,or areas to be cleaned, according to the control command for thecleaning status checking function.

As still yet another example, the controller 140 may receive and outputvoice data or image data in accordance with the video call function, andtransmit any input voice data or image data to the user equipment 100.

The audio input/output unit 150 may receive or output voice information.The audio input/output unit 150 may consist of a microphone, whichreceives voice information and a speaker which outputs voiceinformation.

The image display 160 not only displays image information such as thecleaning area map on the screen, but may also display image informationreceived from the user equipment 100 in accordance with the video callfunction.

The memory 170 may store a plurality of composites of cleaning areainformation, which are generated to have various forms according to theoperation environment. The memory 170 may store the cleaning area map,the feature point map, and the option information, which constitute thecleaning area information as one file or as a plurality of files whichare connected to each other.

The mobile robot 400 may include various sensors, for example, anobstacle sensing sensor and/or a floor sensing sensor. The obstaclesensing sensor may be provided as a contact type sensor or a non-contacttype sensor depending on whether the sensor is to contact with theobstacle, or as a hybrid of the contact and non-contact type sensors.

The contact type sensor refers to a sensor that senses obstacles whenthe mobile robot actually collides with the obstacle.

The non-contact type sensor refers to a sensor that senses an obstaclein advance before colliding with the obstacle or without colliding withthe obstacle and, for example, may include an ultrasound sensor, a photosensor, or an RF sensor.

Even though all components of the exemplary embodiment may be combinedas one component or their operations may be combined, the presentinvention is not limited to the exemplary embodiment. In other words,one or more of all of the components may be selectively combined to beoperated within the scope of the purpose of the present invention.Further, all of the components may be implemented as one independenthardware, but a part or all of the components may be selectivelycombined to be implemented as a computer program which includes aprogram module which performs a part or all of functions combined in oneor plural hardwares. Further, such a computer program may be stored in acomputer readable media such as a USB memory drive, CD disk, or a flashmemory to be read and executed by a computer for implementation of theexemplary embodiment of the present invention. The memory media of thecomputer program may include media such as a magnetic recording mediumor an optical recording medium.

The exemplary embodiments of the present invention which have beendescribed above are examples, and it is obvious to those skilled in theart that various changes or modifications may be made without departingfrom the spirit and scope of the present invention. Therefore, theexemplary embodiments of the present invention are provided forillustrative purposes only, and are not intended to limit the technicalspirit of the present invention. The scope of the technical spirit ofthe present invention is not limited thereto. The protective scope ofthe present invention should be construed based on the following claims,and all the technical concepts in the equivalent scope thereof should beconstrued as falling within the scope of the present invention.

What is claimed is:
 1. A mobile robot comprising: a memory; and acontroller, wherein the controller selects cleaning area informationstored in the memory, recognizes a position of the mobile robot within acleaning area, and causes the mobile robot to clean the cleaning areabased on the selected cleaning area information and the recognizedposition.
 2. The mobile robot of claim 1, wherein the cleaning areainformation includes information obtained from a cleaning area maprepresenting the cleaning area, a feature point map including featurepoint information for the cleaning area, and option information providedby a user of the mobile robot, and wherein the controller selects atleast a portion of each of the information obtained from the cleaningarea map, the cleaning area map, and the option information.
 3. Themobile robot of claim 2, wherein the controller obtains an image of thecleaning area while the mobile robot moves from a first position to asecond position within the cleaning area, extracts a feature point fromthe obtained image to configure a temporary feature point map, comparesthe configured temporary feature point map with the feature point map,and selects the cleaning area information based on the comparison of theconfigured temporary feature point map and the feature point map.
 4. Themobile robot of claim 3, wherein the controller calculates odometryinformation using inertia information obtained according to the movementof the mobile robot from the first position to the second position,predicts a movement point based on the calculated odometry information,compares temporary feature point information obtained at the predictedmovement point with the feature point map obtained from the movementpoint and in the vicinity of the movement point, and determines aposition in the cleaning area map which configures the cleaning areainformation corresponding to feature point information having thehighest matching rate as the comparison result, as the second position.5. The mobile robot of claim 3, wherein when the second position isdetermined, the controller updates the cleaning area map whichconfigures the cleaning area information by an area where the cleaningis completed from the first position to the second position, andcontrols the mobile robot to perform cleaning of the cleaning availablearea from the second position in the updated cleaning area map andupdate the performed result.
 6. The mobile robot of claim 3, wherein thecontroller extracts predetermined geometric information from theconfigured temporary information map and compares the temporary featurepoint map with the feature point map which configures the plurality ofstored cleaning area information based on the extracted geometricinformation to select cleaning area information configured by a featurepoint map having the highest matching rate.
 7. The mobile robot of claim1, wherein when information on a wireless router is received from userequipment, the controller wirelessly connects the mobile robot to thewireless router based on the received information.
 8. The mobile robotof claim 1, wherein the controller operates a first mode for serving asa wireless router which is wirelessly connected to user equipment, whenthe information on the wireless router is received from the userequipment, stops the first mode, and when the first mode stops, operatesa second mode for connecting the user equipment to the wireless routerbased on the received information on the wireless router.
 9. A mobilerobot system, the system comprising: a mobile robot; and a mobileapplication for use with a user equipment to cause the user equipment totransmit a control command to the mobile robot through a wireless routerand receive information on an area where cleaning is completed andcleaning area information while the mobile robot performs cleaning basedon previously stored cleaning area information.
 10. The system of claim9, wherein the user equipment activates the mobile application.
 11. Thesystem of claim 9, wherein the user equipment transmits the controlcommand to the mobile robot in response to the previously storedcleaning area information.
 12. A method for operating a mobile robot,the method comprising: selecting one cleaning area information among aplurality of previously stored cleaning area information according to acontrol command; recognizing a position on a cleaning area map whichconfigures the selected cleaning area information; and updating thecleaning area map by an area where the cleaning is completed as a resultof performing cleaning on a cleaning available area in the cleaning areamap from the recognized position.
 13. The method of claim 12, wherein inthe selecting, an image is obtained while performing cleaning from afirst position to a second position in a predetermined manner accordingto the control command, a feature point is extracted from the obtainedimage to configure a temporary feature point map configured by theextracted feature point, and the configured temporary feature point mapis compared with feature point map which configures the plurality ofstored cleaning area information to select cleaning area informationconfigured by a feature point map having the highest matching rate asthe comparison result.
 14. The method of claim 13, wherein in therecognizing, odometry information is calculated using inertiainformation obtained according to the movement from the first positionto the second position, a movement point is predicted based on thecalculated odometry information, temporary feature point informationobtained at the predicted movement point is compared with the featurepoint map obtained from the movement point and in the vicinity of themovement point, and a position in the cleaning area map which configuresthe cleaning area information corresponding to feature point informationhaving the highest matching rate as the comparison result is determinedas the second position.
 15. The method of claim 14, wherein in theupdating, when the second position is determined, the cleaning area mapwhich configures the cleaning area information is updated by an areawhere the cleaning is completed from the first position to the secondposition, and cleaning on the cleaning available area is performed fromthe second position in the updated cleaning area map and the performedresult is updated.